Limey

The plot thickens: I uncovered some more confusion this afternoon: I could determine that ANY PS fluid, including the Gunk, was the equivalent of the required Audi PS oil. I visited numerous sites for the familiar PS labels. Most said "compatable with Ford, Chrysler, and GM, etc. Valvoline and some others expressly said EXCEPT Audi and Honda. (Honda is yet another variant that doesn't concern us). None of these oils are mineral oils. The reservoirs on both my 96 and 98 say "mineral Oil" and p/n G00-2000.
The fluid I was 'given' about a year ago by the VW dealer bears the p/n G002 012.($13 for 350 mL!) says: Synthetic Blend on the bottle. So what I put in the A6 to top up over the last year was not what should have been in there, at least by the part numbers. I wasn't fast enough to prevent the Gunk oil being put in the car by the mechanic, so tomorrow, we shall drain the system down and put in the 'right' fluid. What was ordered was Pentosin CHF-11s. As far as I can tell, this is completely synthetic, not a blend. From web suppliers, I believe that CHF-7.5 is completely NON synthetic, and that is, by the book, what should be in there. Now I have two web sites worth of info: one says that CHF-11s is the latest and greatest, and was developed for better cold weather performance. (I dont have to worry down here in the south). It also says that the CHF11 can be mixed with CHF7. Another site says specifically NOT to mix them.
So, the questions are: did VW cause my problem by giving me the 'latest' fluid? Is that sythetic blend compatible with mineral oil, or not? Is the synthetic stuf that I am about to put in compatible with the 1996 A6 rack that has just been replaced?
Comments appreciated

A6qwDenver

Pandora's box is what it is.... I've heard all of what you said from sources all around the world.. I stick with the mineral fluid from Blaufergnugen now. There was one exception last year....when my high pressure hose started to go, I used Valvoline High Mileage Synthetic...stopped the leak right away. Drove on it for 3 months before replacing the hose, now I'm back to mineral. Supposedly the PS system seals are conditioned only for mineral fluid, but I gotta believe synthetic can't be that bad for a seal. I think I went back to mineral because the little german devil on my shoulder wouldn't let me rest at night if I didn't follow the big letters that say MINERAL ONLY on the resivoir. So, that probably leaves you no better off, but it's my 2 cents. Good luck.

nbevins

so the safest bet is just to get the synthetic stuff because who knows what was in there before.

20VT90q

Ok people who use the pentosin 11s can refill with either 7.1 or 11 only. The people with the 7.1 can refill with 7.1 only. Just put 11s in there and stop worryng about it. And no you do not want to empty all the fluid and refill with 7.1 because it is hard to get all the 11s completely out of the system. Why search the internet and get confused when we here on the forum can tell you in a short amount of time without hardly any confudion Hope that solved your questions?

Limey

Fair enough, but what is the VW/Audi G00-012 semi-synthetic stuff that VW sold me all about. That fluid is also mixed in (a 100 mL or so) with mineral oil in my A4?

20VT90q

What color was it? There are a lot of sp/s fluids out there? Was it a darker motor oilish color?

20VT90q

No, safest bet is to put the 11s in the system. 7.5 is synthetic, so if you have 11s (mineral) in there(very, very likely considering that's what it had from the factory) it would not be good for it(mineral can only take mineral while synthetic can take both). Remember that if your system has 11s aleady it can ONLY have 11s.

nbevins

http://20v.org/pentosin.htm

I am pretty sure 11s is synthetic. Also what is 7.5? I thought there was only 7.1 which is mineral.

and is the 11 you are talking about the same as 11s in your above post.

20VT90q

Your right I simply mixed the teo up. It's 7.1 not 7.5 too, I got 7.5 from Limey by accident. Sorry about the mistake.

nbevins

no sorrys, glad it was cleared up though...
I really know nothing about the stuff